The present invention relates to method for producing dental replacements wherein a pre-shaped ceramic part is applied to a dental support structure or a tooth stump model by a ceramic paste. The invention also relates to the dental replacement having a pre-shaped ceramic part that is connected by a ceramic paste to a dental support structure or a tooth stump model.
Such a method and such a dental replacement are known from German Offenlegungsschrift 36 04 059. A dental crown according to this publication is produced by first manufacturing a hollow cap and placing the hollow cap with the aid of a mineral dentin replacement material onto a tooth stump, i.e., a tooth stump model. The excess material which is pressed out by pressing the cap onto the tooth stump is removed or shaped and, subsequently, the assembly is fired. This solution is based on the known method of producing porcelain hollow crowns which are connected by tooth cement to the tooth stump model whereby instead of the tooth cement the mineral dentin replacement material is used for connecting the hollow cap to the tooth stump. This is designed to reduce the layer thickness of the hollow cap and to thus improve the esthetic appearance.
The manufacture of hollow caps according to German Offenlegungsschlinfs 36 04 059, however, has been difficult and has shown to be disadvantageous in practice. For example, a plurality of hollow caps with respective color, size, and shape of the desired tooth replacement must be premanufactured and stored so that it is necessary to have an extensive hollow cap supply in storage. On the other hand, the esthetic result is not satisfactory because the external shape of the replacement tooth is always a standard result. The coloration can not accommodate the differentiation of natural teeth even when, for example, the supply of 100 different hollow caps is provided which is necessary for five different colors, five different shapes and four different front teeth.
In contrast, pre-shaped ceramic parts have the advantage that the shaping of the tooth replacement can be individualized while, in contrast, it is essentially predetermined for hollow caps.
Since the hollow cap method has not found acceptance, it has also been suggested to apply multiple ceramic support layers onto a dental support structure or a tooth stump model in sequence in order to allow for an individualized esthetic appearance that closely resembles a natural tooth. The layers can be produced in the dental lab according to an impression. This, for example, known from U.S. Pat. No. 4,473,353 according to which a corresponding layer is applied with an acrylic adhesive after a respective impression has been prepared.
A similarly adhesively connected hollow cap is also known from U.S. Pat. No. 4,813,874. This method also includes producing an impression and does not employ premanufacture so that the work expenditure is relatively great.
It is therefore an object of the present invention to provide a method for producing dental replacements as well as a dental replacement of the aforementioned kind which provides an esthetically pleasing inexpensive tooth restoration which can be produced quickly.